New wine science: A camera that sizes up grapes

Here's the latest technological breakthrough in winemaking: an optical scanner that sorts out grapes of the wrong size, color or shape.

I saw this device in use in Bordeaux last month and it was amazing. Everyone who had one said, "There are only 10 in the world," but I saw four and Christian Moueix told me he has one both in France and at Dominus in Napa Valley.

By next year, there will be a lot more. It's just that great.

Here's how it works. The winemaker shoots a photo of what he considers an ideal grape: size, shape, color. He adjusts the scanner's parameters so that any grape that doesn't measure up will be blown off the belt by a puff of compressed air.

Harvest workers then dump their loads of grapes into the destemmer. The grapes that emerge speed by at 55 mph through the optical scanner. The rejects are blown out faster than the human eye can see. The red vat in the photo is full of reject soup.

I watched this process several times and it's not absolutely perfect -- a few crushed grapes make it through. But I didn't see any stems, miscolored grapes or raisins make it past the scanner. The final sort was more than 99% perfect.

Of course, a traditional sorting table with enough workers can also deliver that kind of quality, possibly even 100%. But that doesn't make the traditional sorting table better for one key reason -- speed. No humans could ever sort grapes this quickly. It's much better to get the grapes destemmed and into fermentation tanks, rather than have boxes of picked grapes back up and warm up while waiting to be sorted.

All the wineries where I saw this machine were delighted with it, and why not? It saves labor, it has huge processing capacity and it does the job. Don't cry for the jobs eliminated -- sorting grapes is only a few days of work per year anyway. Instead, cry with joy for the greater quality wines that will be produced with this thing.

Funny story of man vs. machine: Chateau de Pressac in Saint-Emilion was the first place I saw this thing in use. Owner Jean Francois Quenin said it had just started working again. I wondered if the new machine had malfunctioned.

"A tractor driver drove into it with the year's very first load of grapes," Quenin said. "I guess he didn't expect it to be there." Quenin called the manufacturer and they immediately sent a repairman, who fixed the damage.

A fellow vintner asked, "What happened to the tractor driver? Did you fire him?" Quenin said, "Oh yes." With emphasis. Just like in Terminator, the machines win again.